The average American household spent $51,442 in 2012, the Labor Department said Tuesday. That’s more than the $50,486 spent in 2008, the first time since the recession that average spending has topped its prior peak. Spending bottomed out at $48,109 in 2010.

But the gains in spending haven’t been evenly distributed. Low-income households — those in the bottom fifth of earners, meaning they made less than $19,000 before taxes in 2012 — are still spending less than they were in 2008. Those in the middle three fifths are spending 1.9% more, while the wealthiest 20% — those earning more than $96,000 — are spending 2.4% more.

The contrast is even starker in the past year: The wealthiest households increased their spending by more than 5% in 2012 from 2011, versus a less than 1% uptick in spending for the poorest 20%. (Note: The Labor Department technically counts spending not by household but by “consumer unit,” meaning families and others who share expenses, but not roommates or others who live together but maintain separate finances.)

There’s little mystery as to what’s behind the disparity in spending: a disparity in income. The bottom 20% of earners make on average 4% less, after tax, than in 2008; the top 20% earn nearly 5% more. In fact, the affluent are the only ones to see significant earnings gains: The middle 60% have seen their earnings stay more or less flat since 2008, which means they’ve fallen after adjusting for inflation. That’s hardly surprising, given recent concerns about stagnant wages and the concentration of job growth in low-paying sectors.

The disparity has implications for the broader economy. Wealthier households, by definition, account for a disproportionate share of spending, but they’re playing an even more outsized role right now. The richest 20% spent a combined $2.5 trillion in 2012, $168 billion more than in 2011. That means they accounted for more than 55% of the total increase in spending in 2012.

Moreover, those figures are for all spending. The disparity is likely even greater in terms of discretionary items. The wealthiest households, for example, spent 7% less on housing in 2012 than in 2008, while the poorest households spent 3% more. That likely reflects low interest rates and other factors that have driven down the cost of owning a home, while rising rents are driving up housing costs for renters.

So what did Americans spend more on in 2012? Cars, for one: Spending on vehicle purchases rose more than 20% from 2011. Health insurance, for two: Spending on that category rose 7.2%. And, perhaps less obviously, faith: The average American household gave $734 to churches and religious organizations in 2012, up from $649 in 2011.

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